Archaeologists in Mexico have uncovered a set of ancient rock art during construction linked to a major passenger train project, authorities said. The discovery emerged from fieldwork carried out under the Archaeological Salvage Project tied to the Mexico City–Querétaro train line, overseen by the National Institute of Anthropology and History under the Ministry of Culture.
The site, known as El Venado or Site 77, lies in Hidalgo state near the Tula River and La Requena Dam, close to the communities of San José Acoculco and Benito Juárez. Researchers documented 16 distinct graphic elements spread across two rocky cliffs. These include both carved images, known as petroglyphs, and painted figures.
Initial analysis suggests the artworks span a long period, from prehistoric times to the Postclassic era between 900 and 1521 CE. Some faded figures could date back more than 4,000 years, based on stylistic comparisons.
Human and animal figures offer clues
Several images depict human and animal forms with notable detail. One carving shows a human figure in profile holding a chimalli, or traditional shield, with a stepped design across the chest. Another figure appears to wear a headdress and round eye coverings associated with the rain deity Tlaloc, while holding what seems to be a macana, a wooden weapon.
Archaeologists found 16 petroglyphs and paintings in Hidalgo, Mexico some over 4,000 years old. The rail route was changed to protect the site, showing development and heritage can coexist.#Archaeology #Mexico #History #CulturalHeritage pic.twitter.com/QlOEv6ieYq
— Tom Marvolo Riddle (@tom_riddle2025) April 14, 2026
Additional figures include a human-like form with a feathered headdress and extended limbs, alongside a circular object positioned between the legs. Researchers also identified a carved face with a nose ornament and a deer-like animal. A striking white stripe, formed by removing pigment from a red surface, adds to the variety of techniques observed.
Inside a nearby rock shelter, archaeologists recorded a red-painted human figure and shapes that may represent a serpent or a lightning symbol.
Cultural links and preservation efforts
Further discoveries near the river include a deer figure and a complex human-like image featuring fangs, antennae and bird-like legs. Experts say these traits resemble artistic traditions linked to the Mogollon culture, suggesting possible interaction or shared influences across regions. Another hybrid figure, combining human and animal features, may date to the early colonial period.
Researchers believe mineral and plant-based pigments were used for the paintings, while carvings were created using a stippling method. The site has been documented with photography and photogrammetry to aid detailed analysis and comparison.
The area was first noted in the 1970s during earlier archaeological surveys. Experts suggest the placement of the images may have held ritual or symbolic meaning, possibly tied to cosmology or timekeeping.
In 2025, authorities adjusted the planned rail route after approval from President Claudia Sheinbaum to ensure the site’s protection. Officials said the artworks cannot be moved, underscoring efforts to preserve cultural heritage while allowing infrastructure development to continue.

